Surface Graphitization of Silicon Carbide to Study Divacancy Qubits with Photoexcited Scanning Tunneling Microscopy

Divacancy is a type of defect in silicon carbide (SiC) where a carbon vacancy is adjacent to a silicon vacancy. Divacancy holds electron spin states that serve as qubits with long coherence time even at room temperature. Spatially resolved investigation of dDivacancy qubits with photoexcited scanning tunneling microscopy(STM) can reveal the underlying origin of divacancy qubits. In this talk, we introduce a surface reconstruction graphitization method for SiC to be make it compatible with the STM study. We apply the flashing annealing method to graphitize the surface of SiC and form a large terrace while maintaining the maximum amount of divacancy. We characterize the surface with atomic force microscopy(AFM), Raman spectroscopy, and scanning tunneling microscopy to identify the topography and the number of graphene layers on the surface.